Perceptions of what constitutes a “green” coating are evolving, and it will take more than low and even zero VOC content to make the case for sustainability in architectural coatings as the definition of “green” morphs as well.
|“Cool-roof” coatings will remain a “win-win” sustainable technology, but “thermally responsive” coatings that change color could emerge to generate greater “green” buzz, Lux Research says in its new report, “Painting a Green Future.”|
That’s a key message delivered by a newly issued study, “Painting a Green Future: Opportunities in Sustainable Architectural Coatings,” from Lux Research (Boston, Mass.).
The firm, noting that “greenwashing”—making claims about the environmental attributes of products that don’t stand up to objective scrutiny—can obscure the total environmental impact of materials, says it has developed a “Sustainability Grid” that gives a more complete and accurate picture of a technology’s sustainability profile.
This grid “defines sustainability along three dimensions—environmental impact, energy efficiency and resource efficiency—to create a simple ‘Sustainability Value,’” the firm said in announcing publication of the report.
Comparing this metric with technical value, Lux Research says its analysts “mapped out the technologies that will impact the architectural coatings market.”
“Sustainable coatings technologies reduce the energy, resource and environmental impact of paints and coatings, but often get confused with ‘greenwashed’ unsustainable alternatives,” Aditya Ranade, Lux Research analyst and lead author of the report, says in the firm’s announcement on the study’s publication.
“Sustainable coating technologies are moving beyond low volatile organic compound (VOC) content to include advances in additives like surfactants and coalescing agents, as well as energy-impacting coatings like cool roofs and even solar paints,” Ranade adds.
Winners and Pretenders?
Employing this Sustainability Grid, Lux Research says its analysts identified seven different technologies with “established” green credentials, including elastomeric cool roofs, low-e coatings and paint recycling. Those three types of materials and three others were judged to be “win-win” technologies, with the additional three “win-wins” identified as IR-reflective coatings, 100% solids powder coatings and enhanced hiding-power coatings.
|The “Sustainability Grid” offers an assessment of existing and emerging technologies, based on sustainability and technical value.|
The grid also purports to assess the potential sustainability and technical value of a number of “Emerging Green” technologies, such as solar-energy paint, bio-based materials, UV-cure coatings, self-healing coatings, photocatalytic coatings, and others (see accompanying figure).
Using this Sustainability Grid, Lux Research also categorized various technologies as “Endangered,” “Survivors” and the decidedly less provocative “Voluntary Adoption.”
Ranade, the lead analyst and report author, said in an interview with D+D that “win-win” technologies “offer both technology and sustainability value.” The other categories are described as follows.
• Voluntary Adoption” technologies offer significant sustainability value but are compromised on either performance or cost.
• “Endangered” technologies have negative sustainability impact and questionable technology value.
• “Survivor” technologies will provide enough technical value to the end users and developers to fight rising regulations
Ranade cited “responsive” cool roofs as an example of a “future winner.”
“Thermally responsive coatings that turn from white to black, such as those from Creative Material Technologies and Thermeleon, are set to expand the geographic footprint of cool roofs,” Ranade said. “The technology is years away from becoming mainstream, but has high potential.”
“Traditional cool roofs reduce solar heat gain, thereby reducing air-conditioning loads during summer, but also increase heating loads during winter. According to a 2003 study by the EPA, northern cities such as Chicago show barely above-zero net savings. But New York City shows net savings of 10% to 20% due to high electricity prices in summer, and California shows the greatest net savings of 30% to 40% in cooling costs.”
A “temperature-sensitive” material that is white in summer (i.e. reflecting solar radiation in summer) and “black” in winter (i.e. absorbing solar radiation during winter) “will greatly expand the geographical reach of cool roofs,” he said.
By contrast, solar paints—another “emerging” technology—don’t land in the “win-win” space in the report’s Sustainability Grid, and are “still a long shot,” Lux Research says.
“Several new technologies enable ‘spraying’ of solar cell coatings on buildings, but they suffer from very low (2%) efficiency relative to incumbent solar PV (13% to 15%) and most still remain in labs,” the firm says.
Ranade says these challenges mean “that this is likely to remain a nice curiosity. Most solar paints remain in the laboratories like University of Notre Dame, although a few very early-stage start-ups such as NextGen Solar have emerged in 2011.”
For those interested in shopping for more about Lux Research’s picks for green “winners” and those that are more likely to wither (or at least fade), here’s where to go: www.luxresearchinc.com.
I guess we can get used to roofs changing color, but I was really charged up about paint that turns sunlight into electricity and am a bit disappointed it’s not a sure “win-win.” It loses some of its voltage by being relegated to the “voluntary adoption” zone.
Cool roof coatings;
Comment from Tom Schwerdt, (6/11/2012, 4:18 PM)
Solar paint is a neat concept, but I think that niche will be filled by laminating or adhering thin-film solar, which has already reached 17% cell efficiency in the lab (equivalent conditions to the "solar paint" reaching 2%.) Available in-production modules are more like 12% efficiency.